Christianity in Turkey

Christianity in Turkey has a long history, dating back to the early origins of Christianity in Asia Minor and the Middle East during the 1st century AD. In modern times the percentage of Christians in Turkey has declined from 20 to 25% in 1914, to about 2% in 1927, to 0.2–0.4% today. Sources estimate that the Christian population in Turkey ranges between 203,500 and more than 370,000. However, the exact number remains unclear due to the absence of a religious census in the country. The percentage of Christians in Turkey fell mainly as a result of the late Ottoman genocides: the Armenian genocide, Greek genocide, and Assyrian genocide, the population exchange between Greece and Turkey, the emigration of Christians that began in the late 19th century and gained pace in the first quarter of the 20th century, and due to events such as the 1942 Varlık Vergisi tax levied on non-Muslim citizens in Turkey and the 1955 Istanbul pogrom against Greek and Armenian Christians. Exact numbers are difficult to estimate, as many Turkish former Muslim converts to Christianity often hide their Christian faith for fear of familial pressure, religious discrimination, and persecution.

This was due to events which had a significant impact on the country's demographic structure, such as the First World War, the anti-Christian genocides of Greeks, Armenians, and Assyrians perpetrated by Turkish Muslims, and the population exchange between Greece and Turkey, and the emigration of persecuted Christians (such as Assyrians, Greeks, Armenians, etc.) to foreign countries (mostly in Europe and the Americas) that began in the late 19th century and gained pace in the first quarter of the 20th century, especially during World War I. Signed after the First World War, the Treaty of Lausanne explicitly guarantees the security and protection of both Greek and Armenian Orthodox Christian minorities. Their religious institutions are recognized officially by the Republic of Turkey.

In 2011 according to the Pew Research Center, there were more than 200,000-320,000 people of different Christian denominations in Turkey, representing roughly 0.3-0.4 percent of Turkey's population, including an estimated 80,000 population of Oriental Orthodox Christians, 47,000 Turkish Orthodox Christians, 35,000 Roman Catholic Christians, 18,000 Antiochian Greeks, 5,000 Greek Orthodox Christians, 8,000 Protestant Christians, 4,994 Jehovah's Witnesses, and 512 Mormons. There is also a small group of ethnic Orthodox-Christian Turks (mostly living in Istanbul and İzmir) who follow the Greek Orthodox, Turkish Orthodox, or Syriac Orthodox churches, and additionally Protestant Turks who still face difficulties regarding social acceptance, and also historic claims to churches or property in the country because they are former Muslim converts to Christianity from Turkish–Muslim background, rather than ethnic minorities. Ethnically Turkish Protestants number around 7,000–8,000. In 2009, there were 236 Christian churches open for worship in Turkey. The Eastern Orthodox Church has been headquartered in Constantinople since the 4th century AD.

In 2020 the Anadolu Agency, a state-run news agency of the Turkish government, claimed that the number of Christians in Turkey was 180,854, which corresponds to 0.2% of the population. In a 2022 report of the U.S. Department of State, Christians were seen as being 0.2% of the population. The estimated number of adherents mainly refers to Armenian Orthodox Christians, Armenian Catholics, Chaldean Catholics, Eastern Catholics, Greek Orthodox Christians, Oriental Orthodox Christians, Protestants, and Syriac Orthodox Christians, as well as smaller groups. It was noted that the number of Eastern Orthodox Christians had risen sharply, mainly due to refugees from Russia and Ukraine. In 2024, Freedom House rated the country 2 out of 4 for religious freedom; this was mainly due to disputes over land. The Mor Ephrem Syriac Orthodox church, opened in October 2023, was the first church built since the foundation of the Republic of Turkey.

The Christianization of ancient Assyrians and Armenians most likely began around the 1st century AD. The spread of Christianity beyond Jerusalem is discussed in the Book of Acts.

The Cappadocian Fathers produced some of the earliest hagiographies in the region. In addition to writings about feminine virtue by Gregory of Nyssa and Gregory of Nazianzos; later texts about Nicholas of Sion and Theodore of Sykeon described miracles and rural life.

The historical region of Syria became one of the main centers of miaphisite Christianity, embodied in the Oriental Orthodoxy, which had accepted only the first three ecumenical councils: Nicaea (325), Constantinople (381) and Ephesus (431). Miaphisite Christians were strongly opposed to Chalcedonian Creed that had been established by the Council of Chalcedon in 451. In the 5th and 6th centuries, the Syriac Orthodox Church that originated in Antioch continued to fracture into multiple denominations. Some Armenian miaphysite Christians sought to reunite with Rome in later centuries, but their efforts were unsuccessful.

Constantinople is generally considered to be the center and the "cradle of Orthodox Christian civilization". From the mid-5th century to the early 13th century, Constantinople was the largest and wealthiest city in Europe. The city became famous for its architectural masterpieces, such as Hagia Sophia, the cathedral of the Eastern Orthodox Church, which served as the seat of the Ecumenical Patriarchate, the sacred Imperial Palace where the Emperors lived, the Hippodrome, the Golden Gate of the Land Walls, and opulent aristocratic palaces. The University of Constantinople was founded in the fifth century and contained artistic and literary treasures before it was sacked in 1204 and 1453, including its vast Imperial Library which contained the remnants of the Library of Alexandria and had 100,000 volumes. The city was the home of the Ecumenical Patriarch of Constantinople and guardian of Christendom's holiest relics such as the Crown of thorns and the True Cross. During most of its existence, the Byzantine Empire was one of the most powerful economic, cultural, and military forces in Europe. The imperial role in the affairs of the Church never developed into a fixed, legally defined system. Additionally, due to the decline of Rome and internal dissension in the other Eastern Patriarchates, the Church of Constantinople became, between the 6th and 11th centuries, the richest and most influential centre of Christendom.